The damage to the Studlands Rise court was discovered during an inspection by North Hertfordshire District Council.

Councillor Jane Gray, the district council’s executive member for leisure, said: “We are dismayed to see this occur at such a popular community sports site.

“Every time we have to correct vandalism like this it costs council tax payers money.

“This is money that could be spent elsewhere to deliver services to NHDC residents. Additionally, in this particular instance, the damage could have led to the personal injury of one or more users of the court, potentially giving rise to an even more serious legal claim against the perpetrator.”

The court, which has been there for more than 20 years, is open all year round and is free to use.

A district council spokeswoman told the Crow: “The court is now open and the oil was cleaned up on September 26, the day it was discovered by council staff, in order to minimise disruption for local residents who wanted to use it.”

If you witnessed the vandalism to the tennis courts, call police on the non-emergency number 101.